Photolithography is a common technique used in the manufacture of semiconductor products. Photolithography processes involve the formation of features by using a photo-mask to expose certain regions of a photo-resist layer to light. The exposed or unexposed regions are then developed away to expose a semiconductor layer underneath the photo-resist. The exposed semiconductor layer can then have various processes performed thereon such as etching or doping.
Conventional methods for improving resolution usually include using a quencher, photo decomposable base (PDB) or photo decomposable quencher (PDQ) and a photo-acid generator (PAG) in the photoresist layer. The quencher is a base molecule that can neutralize the acid to quench a chemically amplified reaction (CAR). The PDB or PDQ is a base and typically becomes less basic after exposure. The PAG generates an acid after exposure.
One way to selectively develop regions of a photo-resist material is to expose certain regions to light through a mask. Some masks include scattering bars along the side of various features. The scattering bar helps with the exposure process. Nevertheless, the scattering bars can adversely affect the photo-resist material by blocking light where light should not be blocked. As a result, some or all of the scattering bars can printout onto the underlying area. It is thus desirable to be able to use scattering bars while not causing printout from the scattering bars onto the layer underneath the photo-resist layer.